Wheeled ladder



J. F. PARKINSON.

WHEELED LADDER. APPLICATION HLED MAR. so, 1916. RENEWED OCT. 20,

1,335, 182, v Patented Mar. 30, 1920.

2 SHEETSSHEET 1- IN VEN TOR.

QXJTNEZES; K w Q v W)h/W ATTORNEY J. F. PARKINSON.

WHEELED LADDER.

APPLICATION FILED MAR.30.19I6- RENEWED OCT. 20. 1919.

. 335,182. Patented Mar. 30, 1920.

2 SHEETS-SHEET 2- INVE TOR. z%w BY f MATTORNEY WI TNESSES:

UNITED STATES PATENT OFFICE.

JOHN F. PARKINSON, 0F PALO ALTO, CALIFORNIA.

I i WHEELED LADDER.

Specification of Letters Patent.

Application filed March 30, 1916, Serial No. 87,865. Renewed October 20, 1919. Serial No. 332,103.

To all whom it may concern:

Be it known that I, JOHN F. PARKINSON,

a citizen of the United States, residing at the city of Palo Alto, county of Santa Clara, State of California, have invented a new and useful invention-to wit, Wheeled Ladders; and I do hereby declare the following to be a full, clear, concise, and exact description thereof.

The invention relates more particularly to an improved step ladder having a hinged extension top member which, when not used, may be folded into inoperative and out of the way position, and which when the ladder is in use provides a top portion of considerable area, on which a person can confidently stand and which will support a bucket, basket and the like.

Another object of the invention is to provide a step ladder having wheels and handles which latter may be employed to throw the wheels into and out of operative position, and which provide convenient grips when wheeling the ladder. This wheeling feature is of primary importance and will be found valuable when picking fruit, cleaning windows, and in fact, whenever the ladder be used where frequent moving from place to place is necessary.

Another object of the invention is to provide a ladder so constructed that it may be used safely on inclined surfaces, such as hillsides.

In the specification and the annexed drawings, I disclose the invention in the form which I consider the best but I do not limit myself to such form because the invention may be embodied in other forms, and it is to be understood that in and by the claims following the description herein, I intend to cover the invention in whatever form it may be embodied.

Referring to the annexed drawings, which form a part of this specification:

Figure 1 is a perspective view showing the ladder set up in position ready for wheeling.

Fig. 2 is a perspective View showing the ladder in operative position, with the wheels elevated to allow the supporting frames for the step member to contact with-the ground Fig. 3 is a side elevation of the ladder in its folded position.

Fig. 4 is an enlarged perspective view showing the bidder in the position it asum we e it is s t P n n inc ined ur face, the auxiliary leg extensions being shown in position.

Fig. 5 is a rear elevation of the ladder in its folded position.

Fig. 6 is a fragmentary detail view showing the manner of securing the axle to the ladder and showing by dotted lines the position of the axle when elevated to raise the wheels from contact with the ground.

Fig. 7 is a fragmentary side elevation showing a hinge and its cooperating parts which will be hereinafter described in de tail, and

Fig. 8 is a sectional view on the plane of line 8-8 of Fig. 7.

' Fig. 9 is a view of the supporting attachment used on sloping ground to keep the steps level.

Referring to the drawings by numerals, 1 designates as an entirety the step member having side rails 2 formed with the customary longitudinal slots 3 and supporting between them the steps 1. A supporting frame 5 for the step member 1 is pivotally connected thereto by means of the pivots 6 and the hinge members 7, which are rigidly secured to the side rails 2.

A top extension member 8 is pivotally connected to the hinge members 7 by" the hinge member 9 as clearly shown in the drawings, and this top extension member is Patented Mar. 30, 1920.

adapted to be supported in a plane with the plane of the top 10 by the supporting frame 11, which is p'ivotally connected at its lower end to the lower end of the supporting frame 5 by the pivots 12 and cross pieces 13, which latter are rigidly secured to the sides of the supporting frame 5, as shown in Fig. 6. Hinged braces or struts 14 limit the outward swing of the supporting frame 11 and also prevent it from swinging inwardly toward the frame 5 until the braces 14 are broken. As a further stop for the outward swing of the frame 11, and to better steady and support the top extension memher 8, the hinged sections 9 are-each provided with a lateral outstanding stop 15 adapted to enga e the corresponding side rails of the supporting frame 11.

- Each of the side rails 3 is connected with the corresponding side bar of the supporting frame 5. by a brace-link 16 and lever 17, and the opposed ends of the members are joined by hinge sections 18 and 19, The levers 17 are p v ted int rme te their ends to the side rails 2 and the outer extensions serve as handles when the ladder is being wheeled, folded or unfolded. Referring to Figs. 7 and 8, it is seen that each of the hinge sections 18 and 19 includes a pair of side pieces connected to opposite sides of'its supporting member, and that said side pieces are angular having the laterally extending right angle portions 20, and that the hinge section 19 fits between the side pieces of the hinge section 18. A pivot rod 21 passes through the lateral extensions of both hinges connecting their respective hinge sections and said rod also extends through the upper end of the braces 22, the lower ends of which. are apertured to receive an axle to be hereinafter referred to. Pivoted struts or braces 23 are connected at their lower ends to the pivot rod 21 and at their upper ends to the outer sides of the rails 2 of the step member 1 at a point above the pivot points of the levers 17.

Wheels 25 and 26 are journaled on the axle 27 forming a truck which is connected slidably to the side bars of the frame 5 by retention guides 28, the ends of which are secured to the inner edges of said side bars as shown in Fig. 6. "These retention guides diverge downwardly away from the side bars of the frame 5 and their lower portions are bent at a substantial angle to the body portion thereof, to provide the bottom section 29. To each of the side bars of the frame 5 within the corresponding retention guide 28 there is secured a substantially triangular filler block 30 which forms with the guide a channel 31 for the axle 27. The retension guides are of spring metal and are shaped to spring inwardly at all times and hold the axle in close contact with the filler block.

VVhenthe wheels are beingused to support the weight of the ladder, as occurs when the ladder is being wheeled, the axle is in the position shown in. Figs. 1 and (3, and it is locked in this position by the braces 22. The braces 16 and the levers 17 when in their extended position keep the braces 22 in proper position to retain the axle 27 at the bottom of the channels 31 under the ends of the filler blocks.

. When working with the ladder on hillsides or other inclined surfaces, the top may be maintained in a horizontal plane or substantially so by elevating the wheel 25 which is on the high side to allow the corresponding corner of the supporting frame 5 to contact with the round. This may be accomplished without disturbing the relative position of the other wheel with respect to the frame 5 by breaking the alinement of the brace-link 16 and the lever 17 on the high side of the ladder as shown in Fig. 4-. When thls 1s done the pivot point ofthese members is elevated, drawing the axle 27 from under the filler block 30 on the high side of the ladder, thereby releasing the correspond ing side of the frame 5 and allowing it to drop as shown. An auxiliary leg 32 is connected to the lower side of the step member by means of a U-shaped guide 33 and a bolt and wing-nut connection 34:, the bolt of which passes through the slot 3 in the side rail. The leg extends downwardly below the end of the rail 2 into contact with the ground or a base-board .35 may be provided to give a good foundation for supporting the auxiliary leg. Although notessential I provide a second auxiliary leg 36 for connection to the other side of the step member 1, to engage the base board. 35 as shown, and provide afirm support for the ladder. This base board is preferably" formed" with notches on the upper face to receive the ter-' minals of the auxiliary legs. V 1

Toset up the ladder from its foldedposition as shown in Fig. 3, it is only necessary to grasp the handle extensions of the levers 17 and swing them. forwardly and upwardly, which movement will force the brace rods 22 downwardly and outwardly and at the same time extend the brace-links 16. If sufficient pressure is applied to the handles of the lever 17, the truck axle 27 will be forced into the lower ends of the slots 31 under the filler blocks 30 and the ladder. will assume aposition such as shown in Fig. 1, with theexception of the fact that the extension top is still in its folded position. The top maybe 7 easily thrown into operative position by pulling outwardly on the supporting frame 11 to bring the struts 1 1 into working position. 1

The ladder is now in position for wheel ing or it may be used in the customary manner, but it is preferable to first, before as cending the ladder, drop the frames 5 and 1.1 to contact with the ground, which may be done by breaking the braces 23 and forcing downwardly on the handles of the levers 17 to snap the axle from under the filler blocks 30 up into the channels 31 which allows the rear side of the ladder to drop. 7 r V When it is desired to throw the ladder in position for wheeling after it has been set up as shown in- Fig. 2, it is only necessary'to pull upwardly on the handle of'the lever which will force the truck downwardly under the filler blocks and simultaneously raise the frames 5 and 11.

When thetruck has thus been lowered, the corresponding sections of the braces 23 are thrown into longitudinal alinement'an'd will, when in this position hold the braces 22 in their lowermost position to lock the axle of the truck under the fillerblocks.

From the foregoing description taken in" connection with the accompanying drawings, it will be seen that I have provided a' very. strong, practical andefiicient stepiladder, which may be used to advantage in multifarious pursuits, which will give a large area for the support of a person or an article, and which may be quickly set up in the position for wheeling or for use.

While I have shown and described the preferred embodiment of my: invention, it will be understood that I do not wish to be limited to the exact construction herein shown and described, but as before stated may make such changes as will fall within the scope and spirit of the invention as claimed.

I claim:

1. In combination, a step ladder having a step section and a supporting frame pivoted thereto at its upper end; guide handles pivoted on said step section; braces pivotally connected to said handles; a wheeled,

truck journaled in said braces and slidably connected to the lower end of the supporting frame whereby movement of said handles moves said truck into and from operative position.

2. In combination, a step ladder having a step section and a supporting frame pivoted thereto at its upper end; guide handles piv oted on said step section; brace bars pivotally connected to said handles; a wheeled truck having axles journaled in said brace bars; guide members secured longitudinally to the supporting frame and forming therewith longitudinal channels in which the axles may slide, whereby movement of said handles moves said truck into and from operative position.

3. In combination, a step ladder having a step section and a supporting frame pivoted thereto at its upper end; guide handles pivoted on said step section; brace bars pivotally connected to said handles; a wheeled truck having axles journaled in said brace bars; guide members secured longitudinally to the supporting frame and forming therewith longitudinal channels in which the axle may slide; blocks secured to said frame and forming a bearing for the axle when the ladder is in wheeling position; said wheeled truck being thrown into and from operative position by movement of the guide handles.

4. In combination with a step ladder having a step section and a supporting frame pivotally connected thereto; handles pivotally connected to said step section for moving said ladder; a wheeled truck comprising an axle and wheels journaled in brace bars pivotally connected to said handles, means slidably connecting the axle to the lower end of the supporting frame; means also connected to the supporting frame to form a bearing for the axle when the latter is supporting the ladder, said wheeled truck being thrown into and from operative position by movement of the guide handles.

5. In combination a step ladder having a step section and a supporting frame pivoted thereto at its upper end; guide handles pivoted to said step section and pivotally connected to links pivotally mounted on the supporting member; brace rods pivotally connected to said handles; a Wheeled truck journaled in said brace rods and slidably connected to the lower end of the supporting frame whereby movement of said handles moves said truck into and from operative position. 7

6. The combination with a step ladder having a step section and a supporting frame pivotally connected thereto at one end, of a truck comprising an axle and wheels slidably connected to the lower end of said frame, and means for simultaneously elevating said truck and drawing the frame toward the step member.

7. The combination with a step ladder having a step section and a supporting frame pivotally connected thereto at one end, of a truck comprising an axle and wheels, slidably connected to the'low'er end of said frame, and means for simultaneously elevating said truck and drawing the frame toward the step section, said means comprising a pair of levers pivotally connected intermediate their ends to said step section, a link pivotally connected to the inner end of each of said levers and to the supporting frame, and a brace bar pivotally connected to the inner ends of each of said levers and to the axle of the truck.

8. The combination with a step ladder having a step section and a supporting frame therefor pivotally connected thereto at one end, of a truck having an axle and wheels, slidably connected to said supporting frame near the lower end thereof, of means for simultaneously raising said truck and swinging the supporting frame toward the step section, and means for locking said first mentioned means in extended position.

In testimony whereof, I have hereunto set my hand at San Francisco, California, this 20th day of March, 1916.

JOHN F. PARKINSON.

In presence of BALDWIN VALE. 

